Study On The Synthesis And Application Of A Novel Cationic Fatty Amide Sizing Agent

In this paper, the condensation reaction took place between stearic acid and diethylene triamine, then a novel cationic fatty amide sizing agent was prepared by the mean of crosslinking reaction with the addition of epichlorohydrin. The results showed:First, the optimum synthetic conditions for fatty amide sizing agent were: n(stearic acid): n(diethylene triamine)=2:1, the reaction time was 6hours, the reaction temperature was 180℃,n(intermediate products):n(pichlorohydrin)=1:1.05,the reaction time was 3hours, the reaction temperature was 80℃.Secondary, fatty amide sizing agent is a kind of cationic synthesized surfaced sizing agent with branched chains, the color appears to be milky, the solid content is 15%. The home-made sizing agent was structurally confirmed by Fourier transform infrared spectrum technique, the surface morphology, the fracture surface morphology and the connecting condition of the fiber on paper after sizing were also studied from microcosmic point of view by Scanning electron microscope (SEM), the comprehension with macroscopic performance of paper was improved.Thirdly, the effect content of the surface sizing agent, sizing content, sizing temperature, pH value, on paper properties had been investigated. The optimum condition as follows: the best content of the surface sizing agent was n(oxidized starch):n(fatty amide)=95:5, sizing content was 2.0g/m2, sizing temperature was 70℃, pH value was between 4.5 and 5.5. Under this condition, the strength performance of the paper that after sizing was enhanced.Fourthly,in the system of amide internal sizing, when the dosage of CS was 0.75%, the dosage of CPAM was 0.03%, and the dosage of fatty amide was 0.25%, the strength performance of the paper was the best.Fifthly, the stability of fatty amide was researched. Compared with AKD, the stability of fatty amide was better, it will not hydrolyzed in high temperature storage, also it is no need to cured after fatty amide, so the lagging phenomenon of the sizing degree is not exist.Oxidized starch, AKD and fatty amide used for surface sizing were also investigated. Home-made fatty amide sizing agent had excellent behavior. It could enhance the surface strength, smoothness, water-resistance of paper. Under the same dosage of sizing, sizing effect of AKD was enhanced by 1%, fatty amide was better than AKD and oxidized starch for enhancing smoothness and surface strength performance of paper. For using fatty amide, smoothness was enhanced by 2% and 29%, surface strength performance was enhanced by 3% and 38% compared with AKD and oxidized starch.